Al-Qūhī's perfect compass to draw conic sections Pregar Ta'm
Abū Sahl Wayjan ibn Rustam al-Kūhī (al-Qūhī;Persian:ابوسهل بیژن کوهیAbusahl Bijan-e Koohi) was aPersian[1][2]mathematician,physicist andastronomer. He was from Kuh (or Quh), an area inTabaristan,Amol, and flourished inBaghdad in the 10th century. He is considered one of the greatest geometers, with many mathematical and astronomical writings ascribed to him.[3][4][5]
Engraving of al-Qūhī's perfect compass to draw conic sections
Al-Qūhī was the leader of the astronomers working in 988 AD at the observatory built by theBuwayhid amirSharaf al-Dawla in Badhdad. He wrote a treatise on theastrolabe in which he solves a number of difficult geometric problems.
^Suter,Die Mathematiker und Astronomen der Araber (75-76, 1900). In his treatise On Rising Times, he wrote that he had also investigated astronomy as well as centers of gravity and optics. His Perfect Compass, for example, represented a step beyondIbn Sina’s pointwise constructions of conic sections and described an instrument al-Qūhī characterized as useful for drawing these sections on sundials and astrolabes.
^Jan Hogendijk (1984) "al-Kuhi's construction of an equilateral pentagon in a given square",Zeitschrift für Gesch. Arab.-Islam. Wiss. 1: 100-144; correction and addendum Volume 4, 1986/87, p.267
^Jan Hogendijk (2008) "Two beautiful geometrical theorems by Abu Sahl Kuhi in a 17th century Dutch translation",Ta'rikh-e Elm: Iranian Journal for the History of Science 6: 1-36
^Rashed, Roshdi (1996).Les Mathématiques Infinitésimales du IXe au XIe Siècle1: Fondateurs et commentateurs: Banū Mūsā, Ibn Qurra, Ibn Sīnān, al-Khāzin, al-Qūhī, Ibn al-Samḥ, Ibn Hūd. London.{{cite book}}: CS1 maint: location missing publisher (link) Reviews: Seyyed Hossein Nasr (1998) inIsis89 (1) pp. 112-113JSTOR236661; Charles Burnett (1998) inBulletin of the School of Oriental and African Studies, University of London61 (2) p. 406JSTOR3107736.
^John Lennart Berggren, Hogendijk:The Fragments of Abu Sahl al-Kuhi's Lost Geometrical Works in the Writings of al-Sijzi, in: C. Burnett, J.P. Hogendijk, K. Plofker, M. Yano (eds):Studies in the History of the Exact Sciences in Honour ofDavid Pingree, Leiden: Brill, 2003, pp. 605–665
^Mohammed Abattouy (2002), "The Arabic Science of weights: A Report on an Ongoing Research Project",The Bulletin of the Royal Institute for Inter-Faith Studies4, p. 109-130
^Berggren: "The correspondence of Abu Sahl al-Kuhi and Abu Ishaq al-Sabi: a translation with commentaries",J. Hist. Arabic Sci., volume 7, 1983, pp. 39-124.
^M. Steinschnieder,Lettere intorno ad Alcuhi a D. Bald. Boncompagni (Roma, 1863)
